Alcohol's possible benefits for the brain - news reports
About these topic collections
I’ve been reporting on memory research for over ten years and these topic pages are simply collections of all the news items I have made on a particular topic. They do not pretend to be in any way exhaustive! I cover far too many areas within memory to come anywhere approaching that. What I aim to do is provide breadth, rather than depth. Outside my own area of cognitive psychology, it is difficult to know how much weight to give to any study (I urge you to read my blog post on what constitutes scientific evidence). That (among other reasons) is why my approach in my news reporting is based predominantly on replication and consistency. It's about the aggregate. So here is the aggregate of those reports I have at one point considered of sufficient interest to discuss. If you know of any research you would like to add to the collection, feel free to write about it in a comment (please provide a reference).
Older news items (pre-2010) brought over from the old website
Regular moderate alcohol intake has cognitive benefits in older adults
A six-year study involving over 3,000 seniors (75+) has found that for those who had no cognitive impairment at the start of the study, moderate drinking (1-2 drinks a day) was associated with a 37% reduction in risk of developing dementia compared to individuals who did not drink at all. The type of alcohol didn’t matter. However, for those who started the study with mild cognitive impairment, any consumption of alcohol was associated with faster rates of cognitive decline. Moreover, heavy drinkers were almost twice as likely to develop dementia during the study. The results are consistent with previous studies of middle-aged adults that suggest mild to moderate alcohol intake may reduce the risk of dementia, except in the case of individuals who already have mild to moderate cognitive impairment.
Sink, K.M. et al. 2009. Moderate alcohol intake is associated with lower dementia incidence: results from the Ginkgo Evaluation of Memory Study (GEMS). Presented at the Alzheimer's Association International Conference on Alzheimer's Disease July 11-16 in Vienna.
Moderate drinking can reduce risks of Alzheimer's dementia and cognitive decline
A review of 44 studies has concluded that moderate drinkers often have lower risks of Alzheimer's disease and other cognitive loss. Moderate alcohol consumption generally is defined as 1 drink or less per day for women and 1-2 drinks or less per day for men.
 Alcohol in Moderation, Cardioprotection, and Neuroprotection: Epidemiological Considerations and Mechanistic Studies. Alcoholism: Clinical and Experimental Research. 33(2), 206 - 219.(2009).
Chocolate, wine and tea improve brain performance
A study of over 2000 older Norwegians (aged 70-74) has found that those who consumed chocolate, wine, or tea had significantly better cognitive performance and lower risk of poor cognitive performance than those who did not. Those who consumed all 3 studied items had the best performance and the lowest risks for poor test performance. The associations between intake of these foodstuffs and cognition were dose dependent, with maximum effect at intakes of around 10 grams a day for chocolate and around 75–100 ml a day for wine, but approximately linear for tea. The effect was most pronounced for wine and modestly weaker for chocolate intake. The finding is consistent with research indicating that those who consume lots of flavonoids have a lower incidence of dementia.
 Intake of flavonoid-rich wine, tea, and chocolate by elderly men and women is associated with better cognitive test performance. The Journal of Nutrition. 139(1), 120 - 127.(2009).
Red grape seeds may help prevent Alzheimer's disease
Research into the nearly 5000 compounds contained in red wine to reveal the source of the health benefits seen from red wine has revealed that polyphenols derived from red grape seeds may be useful agents to prevent or treat Alzheimer's disease. Red grape seeds currently being developed with the name of Meganatural AZ were found to significantly reduce cognitive deterioration in genetically engineered mice, by preventing the formation of amyloid beta. The mice were given the extract before the age at which they normally develop signs of disease, suggesting the extract may help prevent or postpone the development of Alzheimer’s. The major polyphenol components in the grape seed extract product are catechin and epicatechin, which are also abundant in tea and cocoa. Unlike the polyphenol resveratrol, which has been shown to have similar effects, but requires extremely high doses, the catechins appear to be effective at much lower doses. Further research will of course be needed before human recommendations can be made.
 Grape-Derived Polyphenolics Prevent Aβ Oligomerization and Attenuate Cognitive Deterioration in a Mouse Model of Alzheimer's Disease. The Journal of Neuroscience. 28(25), 6388 - 6392.(2008).
Why moderate drinking may boost memory
Another study has come out suggesting moderate amounts of alcohol are good for the brain, and explaining why. The rat study found that low levels of alcohol increased the expression of a particular receptor, NR1, on the surface of neurons in the hippocampus. Increasing the number of NR1 receptors in a different group of rats resulted in a memory boost similar to that seen in the rats given low doses of alcohol. There were no toxic effects of low-level alcohol consumption (1—2 drinks a day) on the brain, but a higher dose of alcohol did damage neurons.
The findings were presented at the Society for Neuroscience's annual meeting on October 14-18 in Atlanta, Georgia.
Cabernet sauvignon red wine reduces the risk of Alzheimer's disease
A mouse study has found moderate consumption of the red wine Cabernet Sauvignon significantly reduced Alzheimer’s-type deterioration of spatial memory function. The Cabernet Sauvignon used contained a very low content of resveratrol, 10-fold lower than the minimal effective concentration shown to promote Aß clearance in vitro. It is suggested that, instead, the benefit occurred through promoting non-amyloidogenic processing of amyloid precursor protein. The finding supports epidemiological evidence indicating that moderate wine consumption (one drink per day for women and two for men) may help reduce the relative risk for Alzheimer’s.
 Moderate consumption of Cabernet Sauvignon attenuates Aß neuropathology in a mouse model of Alzheimers disease. The FASEB Journal. 20(13), 2313 - 2320.(2006).
Moderate alcohol intake associated with better mental function in older women
A study of over 7,000 older women (65-80) found that those who drink a moderate amount of alcohol have slightly higher levels of mental function than non-drinkers, particularly in verbal abilities. The researcher warned that "Until we better understand the reasons why alcohol consumption is associated with better cognitive functioning, these results on their own are not a reason for people who don't drink to start or for those who drink to increase their intake."
 Association between alcohol intake and domain-specific cognitive function in older women. Neuroepidemiology. 27(1), 1 - 12.(2006).
More support for benefits of some alcohol
A longitudinal study of an elderly community sample found that, over an average of 7 years, mild-to-moderate drinking was associated with less average decline in cognitive function compared to not drinking.
 Alcohol consumption and cognitive function in late life: A longitudinal community study. Neurology. 65(8), 1210 - 1217.(2005).
Moderate alcohol intake may reduce cognitive decline in older women
Two recent large-scale epidemiological studies have come out recently with similar findings. Data from the Women's Health Initiative Memory Study (involving 4,461 women aged 65 to 79 years) has revealed that women who reported having one or more alcohol drinks daily had a 40% lower risk of significant declines in cognitive function over time, compared to women who reported no alcohol intake. It is possible that moderate alcohol intake may reduce the risk for narrowed vessels in the brain. In addition, alcohol may decrease the formation of plaque that is associated with Alzheimer's disease.
Data from the Nurses' Health Study, begun in 1976 and involving 12,480 women, now aged between 70 and 81 years old, has found that women who had the equivalent of one drink a day had a 23% lower risk of becoming mentally impaired during a two-year period, compared with non-drinkers. It made no significant difference whether they drank beer or wine.
 Association between Reported Alcohol Intake and Cognition: Results from the Women's Health Initiative Memory Study. Am. J. Epidemiol.. 161(3), 228 - 238.(2005).
 Effects of Moderate Alcohol Consumption on Cognitive Function in Women. N Engl J Med. 352(3), 245 - 253.(2005).
Drinking too much alcohol, and not enough, increases risk of cognitive impairment
In Finland, researchers re-examined 1018 participants from a study of 1464 men and women aged 65-79 studied in 1972 or 1977. They found that participants who drank no alcohol in midlife as well as those who drank alcohol frequently were twice as likely to have mild cognitive impairment in old age compared to those who drank alcohol infrequently. The effect of alcohol was however modified by the presence of the apolipoprotein e4 allele (implicated in dementia risk). People who were carriers of the apolipoprotein e4 allele had an increased risk of dementia with increasing alcohol consumption, with carriers of the gene significantly reducing their risk by never drinking.
Possible benefits of alcohol in reducing cognitive decline
Another report from the Whitehall Study database. This one adds to the, still controversial, research linking moderate wine consumption with health and longevity. Of those who reported drinking alcohol in the past year, those who consumed at least one drink in the past week were significantly less likely to have poor cognitive function than those who did not. These benefits appeared even at levels of alcohol consumption that most sensible observers would consider excessive, and emphasizes once again that correlation is not causation. It seems likely that this association at least partly reflects other factors, and indeed, the correlation was reduced when social position was taken account of. It may also reflect the possible effect of alcohol in reducing risk of cardiovascular disease.
Alcohol's benefits for cognition may be overstated
Some studies (that receive a lot of media attention) have suggested that moderate alcohol drinking may have beneficial effects on the heart or the brain. Other studies have found no effect, or a negative one. Now a new study may provide an answer to the conflicting results. Using data from the Wisconsin Longitudinal Study, which has followed more than 10,000 men and women who graduated from Wisconsin high schools in 1957, researchers in 1992 asked the participants about their drinking habits. It was found that men who consumed low levels of alcohol in 1992 had higher scores on the abstract reasoning test than those who drank either more or less. However, when earlier cognitive ability (measured in high school) was taken into account, the difference between non-drinkers and those who had one drink a day disappeared. With the women, both non-drinkers and heavy drinkers had lower scores at age 53 than moderate drinkers. But when adolescent cognitive ability was taken into account, these differences disappeared. Participants will be re-examined next year, when they’re about 65.
 Alcohol Use and Cognition at Mid‐Life: The Importance of Adjusting for Baseline Cognitive Ability and Educational Attainment. Alcoholism: Clinical and Experimental Research. 27(7), 1162 - 1166.(2003).
Drinking wine may lower risk of dementia
Researchers in Copenhagen have followed up an analysis of drinking patterns for wine, beer and liquor of 1,709 people in the 1970s with an assessment of dementia in the 1990s, when participants were age 65 or older. 83 of the participants had developed dementia. Their alcohol intake was compared to that of those who did not develop dementia. It was found that those who drank wine occasionally had a lower risk of developing dementia, including Alzheimer's disease. Those who drank wine every day were no more or less likely to develop dementia than those who drank it less often. The study also found that occasional beer drinking was associated with an increased risk of developing dementia. It is important to note that eating habits were not investigated, and research suggests that wine drinkers may have better dietary habits than beer and liquor drinkers.
 Amount and type of alcohol and risk of dementia. Neurology. 59(9), 1313 - 1319.(2002).
Moderate alcohol consumption may help prevent dementia
Recent research has suggested that moderate alcohol consumption may have positive health benefits for cardiovascular and cerebrovascular functioning. Given the connection between dementia in old age and cerebrovascular disease, a recent Italian study analyzed data from 15,807 patients (65 years of age or older) to assess whether there is any link between alcohol consumption and cognitive function. Signs of cognitive derangement were found in 19% of the participants who reported regular alcohol consumption, and in 29% of those who abstained from alcohol. The quantity of daily alcohol consumption was an important factor. The risk of cognitive impairment was reduced among women whose daily alcohol consumption was less than 40 grams and among men who drank less than 80 grams. Higher levels of alcohol consumption showed an increased risk of cognitive impairment when compared with both abstainers and moderate drinkers.
 Dose-Related Impact of Alcohol Consumption on Cognitive Function in Advanced Age: Results of a Multicenter Survey. Alcoholism: Clinical and Experimental Research. 25(12), 1743 - 1748.(2001).
A Dutch study suggests that light-to-moderate alcohol consumption could reduce the risk of dementia among older people. Light-to-moderate alcohol consumption (1 to 3 drinks per day) was associated with a 42% risk reduction of all dementia, and around a 70% reduction in risk of vascular dementia.
 Alcohol consumption and risk of dementia: the Rotterdam Study. The Lancet. 359(9303), 281 - 286.(2002).